Detailed Structure and Stabilization Mechanism of Lifted Laminar Methane Flame

Abstract

The present study has numerically investigated the lifted flame field frequently encountered in the actual fire situations. This study employs the physical submodels including the detailed chemical kinetics, the variable transport properties, and the radiation model. A lifted laminar CH4/air flame with a central diluted fuel jet and a surrounding fuel-lean coflow is chosen as a validation case. Computations are done for three models which include the detailed chemistry model considering the radiative heat loss, the detailed chemistry model neglecting radiation, and the single-step irreversible chemistry considering radiation. Among three models, the detailed chemistry model considering the radiative heat transfer yields the best conformity with the measured velocity distribution. Numerical results indicate the present approach well captures the detailed structure and stabilization mechanism of the partially premixed triple flame.

Keywords

flame stabilization lifted flame partially premixed mixture detailed chemistry variable transport properties

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